Sausage making may include (1) ground, fresh sausage products, (2) emulsion-type sausages, such as frankfurters, wieners, bologna, liver sausage, (3) fermented sausage products. The production of sausage dates back centuries. Traditionally, in one embodiment, meat in an emulsion in a semi-solid form is stuffed into a natural or artificial casing, such as a collagen casing comprising animal protein. Collagen casings are made from a naturally occurring protein, typically bovine collagen from the animal hide is used, and may be edible.
Casings for sausage and other meat products may be natural or artificial. Natural casings are sometimes eaten and sometimes peeled off before being eaten and comprise intestines of animals. Artificial or sometimes called manufactured casings fall into two categories. They may be made from natural materials, such as cellulose collagen, artificial (synthetic) materials, such as thermoplastics or polymers. Manufactured casings from artificial materials include those casings made from cellulose from plants or alginate from seaweed or those casings made from collagen found on the underside of the hide of some animals. Typically, structural and functional elements of a system for making sausage or other coated and extruded meat product depend on the type of casing used and often machinery used where one type of casing is not suitable for another type of casing. One type of casing is made from collagen, which is obtained from the corium layer of selected split cattle hides. Collagen casings are substantially permeable for smoke and water vapor.
There are a number of problems associated with the system of sausage making using collagen as set forth hereinabove. One problem is the physical size of the machinery required and a second problem is the cost and maintenance of the machine. As regards to the size, the prior art, especially the pre-dry (pre-dry meaning before the smoking step) described above, requires a machine that is huge, both in the longitudinal and vertical dimensions, but especially in the vertical dimension. Prior art pre-dry (before smoking) typically uses a serpentine system of baskets, which has multiple chains and gears, typically thousands of gears and a hundred or more baskets. The maintenance alone on such systems may be hundreds of thousands of dollars a year. What the prior art lacks is a mechanical system that has a limited vertical profile, which also lacks gears and baskets.
The time that the standard sausage making processes take is long and the machines used are large and complex, covering a large area. In an effort to reduce time and complexity, Applicant provides a new process indicated at FIG. 1.
Emulsion-type sausage making may be done by a process to co-extrude a strand of sausage material, which has an inner core of meat emulsion and an outer surface material that can be coagulated to provide an encasement for the strand. The outer surface material may consist of a gel comprising collagen protein. Coagulation of the collagen normally includes subjecting the extruded strand to a brine (salt) solution. Coagulation as used herein means the step or steps of firming up or hardening and stabilization of the casing. This is primarily done in two ways. First, by removal of water from the collagen gel and, second, by cross-linking the collagen fibers.
Collagen can be set by known methods in the preparation of artificial sausage casing. Co-extrusion takes place into a brine setting bath. Under the influence of the setting bath or solution, the collagen is at least partly coagulated or set in contact with the extruded food stuff and the formed coated food stuff then emerges from the bath to undergo further process steps. Stabilization may, however, be by other means, for example, air drying.
Drying of collagen seems to stabilize the food products. Fibrous materials, such as collagen casing, may be convection dried as in the prior art, which is slow and expensive. The convection drying apparatus of the prior art uses many baskets and convective hot air. During convective drying, the water filled pores of the collagen structure collapse because of capillary forces. The collagen chains begin to stick together.
Collagen is naturally cross-linked. Collagen may be further cross-linked by chemical cross-linkers (such as those found in liquid smoke), enzymes, metallic ions or other mechanisms. Cross-linking may also be achieved by physical methods, such as UV, temperature treatment, and dry state, radiation, and electron beam. Cross-linking decreases solubility and susceptibility to enzymes and microbial attack.
The process for producing co-extruded collagen encased food product, such as meat products and sausage, typically includes the extrusion of a meat emulsion with an amount of collagen gel. In a current process for making co-extruded sausage and links, coarse ground emulsion is stuffed through a stuffing horn in a co-extrusion head. The emulsion is co-extruded with vacuumed collagen gel, which is typically about 4 to 5% collagen at 4% solids.
One current step in the manufacturing of sausage by co-extrusion occurs when the meat product (typically in the form of a semi-solid emulsion) is coated with a collagen gel to produce a meat product. The meat product is then subject to a solution, for example, a brine salt that begins dehydration, which starts coagulation or setting of the collagen gel. The brine usually provides sufficient set or firmness for the subsequent linking and cutting steps to cut the product into links. The partial dehydration helps collapse the collagen onto the emulsion. Yet the casing continues to be rehydrated during this step due, in part, to rehydration of the collagen from the inside—that is, from moisture in the meat emulsion.
The brine solution of this step may be about 22 to 26% salt dissolved in tap water. This resident time for the product may be about 18 to 24 seconds to bring about sufficient dehydration for cutting and linking. The brine may be at ambient temperature. Following the brine step, the linear (coaxial) meat product is conveyed through a crimper wheel or other suitable device to link and cut the sausage to lengths and then the product is conveyed to a pre-dry (measuring before the smoking step), rocker basket serpentine system.
The sausage is pre-dried in a rocking basket system at about 150° F. to about 170° F., with low humidity (typically about 5 to 20%), to evenly dry the product and keep the product round. The pre-dry time is typically about 20 to 30 minutes. This is typically done in a huge machine, due to the slow hot air heating required to sufficiently dry the food product. It has rocking baskets to heat evenly the individual product items and keep them round.
Typically, following pre-drying (meaning before smoking), the smoke and cross-link step occurs. The sausage links are transferred from the pre-dry baskets to the smoking baskets and run through a liquid smoke, dying and cross-linking solution. The time in the partial submersion and/or deluge bath is typically about 10 to 15 seconds. The liquid smoke solution is at about 110° F. to 120° F.
Following the smoke and cross-link, the post-drying (meaning after smoking) step is carried out. The sausage links are post-dried on a conveyor belt at about 150° F. to 170° F. with low humidity. This will help cross-link the collagen and develop or set the color. Post-drying typically runs about 8 to 12 minutes, with the links at about 120° F. to 130° F. (oven convective air temperature) before going to the vacuum packaging machine.